when I downloaded all Amazon apps to my s9+, they won't even open, the only one that did open was the amazon shopping app but it won't let you log in! are they not compatible yet? Very frustrating.
Where did you download them from? Are you sure they're the latest version? I just set mine up last night and I just tested Amazon Shopping and Prime Video. No issues logging in or playing videos or accessing the app. T-Mobile variant.
I am having the same problem. I transferred my Kindle app from by S6 and it seemed to work but didn't show any content. I uninstalled and reinstalled from Play Store and I now just get a black screen when I run Kindle. I tried to install the Amazon App and it wouldn't let me log in. The app I loaded from play store said that the "the specific device could not be authenticated." The app I loaded from the Amazon site just said error 10.
Same thing happened to me with Amazon Shopping and Kindle app. The Kindle app just gives a black screen. I am waiting to hear back from Amazon support.
Are both of your devices unlocked? Or maybe the same carrier? Or maybe a bug if transferring the app from a different device? (I used Smart Switch to transfer everything BUT apps, maybe that made a difference).